var
fs = require('fs'),
url = require('url'),
path = require('path'),
http = require('http');

// 从命令行参数获取root目录，默认是当前目录:
var root = path.resolve(process.argv[2] || '.');

console.log('Static root dir: ' + root);

// 创建服务器:
var server = http.createServer(function (request, response) {
// 获得URL的path，类似 '/css/bootstrap.css':
var pathname = url.parse(request.url).pathname;
// 获得对应的本地文件路径，类似 '/srv/www/css/bootstrap.css':
var filepath = path.join(root, pathname);
// 获取文件状态:
fs.stat(filepath, function (err, stats) {
    if (!err && stats.isFile()) {
        // 没有出错并且文件存在:
        console.log('200 ' + request.url);
        // 发送200响应:
        response.writeHead(200);
        // 将文件流导向response:
        fs.createReadStream(filepath).pipe(response);
    } else {
        // 出错了或者文件不存在:
        console.log('404 ' + request.url);
        // 发送404响应:
        response.writeHead(404);                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
        response.end('404 Not Found');
    }
});
});

server.listen(8080);

console.log('Server is running at http://127.0.0.1:8080/');